1. Field of the Invention
This invention relates generally to occupancy status monitoring and signaling systems.
2. Prior Art
In many office environments, the occupancy of tall cubicles and enclosed offices cannot be ascertained from a distance. A worker looking for another worker must walk to a cubicle or office to see if the person is there. Time is wasted when after all the walking, the person being sought is not in the cubicle or office. Further, a person being threatened with physical violence or experiencing a medical emergency may not be able to signal for help from other workers from within the confines of a cubicle or office.
Various devices for indicating occupancy in a room are known. U.S. Pat. No. 5,371,489 to Carroll et al. discloses a motion detector that activates a constant white light and a flashing red light upon detecting motion. However, it cannot detect the presence of a stationary person, so it may turn off the lights when the room is still occupied. In practice, this problem may be reduced by turning on the lights for a predetermined time after detection of motion. However, if a person leaves the room shortly after triggering the lights, the lights may stay on to indicate occupancy erroneously. Further, the light signals can only been seen by nearby people or those with a direct line of sight, but they cannot be seen by people in other cubicles or in other rooms. U.S. Pat. No. 4,476,461 to Carubia discloses an occupancy indicator that includes switches for monitoring occupancy in remote locations. Signals from the switches are transmitted to an occupancy information recorder through a communication circuit. However, it does not provide a visual indication of occupancy at the locations being monitored. U.S. Pat. No. 4,340,879 to Laflamme shows a device for indicating the presence of workers. It includes a plurality of indicators that are individually and manually operated to indicate if a corresponding person is in or out. It is for being used in a reception area. It does not provide automatic detection of occupancy in cubicle and rooms. U.S. Pat. No. 3,964,058 to Winston shows a lighted "Do Not Disturb" sign which is manually operated. It also does not provide automatic detection of occupancy in cubicle and rooms.